I have this motor on my 13' Tunnel Hull. I have a Faria Beede Tach on there. It says setting 4 is correct for my motor. It runs up to about 5500rpm at about 48mph. And then it jumps up to about 6800-7000 rpms at that speed. I don't know if the prop starts slipping or not, but if I trim it up or down while at WOT, it will drop back to 5500rpm until I release the trim switch and it goes back to nearly 7000rpm. I don't notice any change in motor sound when that happens. I put a little cheap digital tach on it for comparison. That one pretty much stays at around 5500rpm at WOT. Both tachs basically match up to 5500rpm.
My trim is an electric Trim Tab actuator, so I imagine it has a significant current draw. I don't know if that can affect the tach reading or not. It runs off of a fuse block that's fed with 30 amps and has only a couple gauges running off it otherwise.
How long can I run this motor at nearly 7000 rpm before it craps out? I've run it 6 or 7 twenty minutes test trips at that speed and it doesn't show any ill effects from it. What's going on?
Stephen
My trim is an electric Trim Tab actuator, so I imagine it has a significant current draw. I don't know if that can affect the tach reading or not. It runs off of a fuse block that's fed with 30 amps and has only a couple gauges running off it otherwise.
How long can I run this motor at nearly 7000 rpm before it craps out? I've run it 6 or 7 twenty minutes test trips at that speed and it doesn't show any ill effects from it. What's going on?
Stephen